University of Haifa

About: University of Haifa is a education organization based out in Haifa, Israel. It is known for research contribution in the topics: Population & Poison control. The organization has 7558 authors who have published 27141 publications receiving 711629 citations. The organization is also known as: Haifa University & Universiṭat Ḥefah.

Hardness and Algorithms for Rainbow Connection

Abstract: An edge-colored graph $G$ is {\em rainbow connected} if any two vertices are connected by a path whose edges have distinct colors. The {\em rainbow connection} of a connected graph $G$, denoted $rc(G)$, is the smallest number of colors that are needed in order to make $G$ rainbow connected. In the first result of this paper we prove that computing $rc(G)$ is NP-Hard solving an open problem from \cite{Ca-Yu}. In fact, we prove that it is already NP-Complete to decide if $rc(G)=2$, and also that it is NP-Complete to decide whether a given edge-colored (with an unbounded number of colors) graph is rainbow connected. On the positive side, we prove that for every $\epsilon >0$, a connected graph with minimum degree at least $\epsilon n$ has {\em bounded} rainbow connection, where the bound depends only on $\epsilon$, and a corresponding coloring can be constructed in polynomial time. Additional non-trivial upper bounds, as well as open problems and conjectures are also presented.

The hijacking of a receptor kinase-driven pathway by a wheat fungal pathogen leads to disease

Abstract: Necrotrophic pathogens live and feed on dying tissue, but their interactions with plants are not well understood compared to biotrophic pathogens The wheat Snn1 gene confers susceptibility to strains of the necrotrophic pathogen Parastagonospora nodorum that produce the SnTox1 protein We report the positional cloning of Snn1, a member of the wall-associated kinase class of receptors, which are known to drive pathways for biotrophic pathogen resistance Recognition of SnTox1 by Snn1 activates programmed cell death, which allows this necrotroph to gain nutrients and sporulate These results demonstrate that necrotrophic pathogens such as P nodorum hijack host molecular pathways that are typically involved in resistance to biotrophic pathogens, revealing the complex nature of susceptibility and resistance in necrotrophic and biotrophic pathogen interactions with plants

Work commitment, job satisfaction, and job performance: an empirical investigation

Abstract: This study examines the relationships between joint work commitments, job satisfaction, and job performance of lawyers employed by private law firms in Israel. Based on Morrowʼs (1993) concept of five universal forms of commitment, their interrelationship was tested with respect to the commitment model of Randall and Cote (1991), which appeared to show in previous studies (Cohen, 1999, 2000) a better fit compared to other models. In addition, the study examined the relationship between the commitment model and work attitude and outcome, namely, job satisfaction and job performance. The results show that the commitment model of Randall and Cote was almost fully supported, except for the relationship between job involvement and continuance commitment. This relationship is better understood via career commitment. An interesting finding of this study is that job satisfaction has a mediating role in the relationship between joint work commitment and job performance. The article concludes with suggestions regarding further investigation of the interrelationships between work commitment constructs, and the relationship between joint commitment forms, job satisfaction, and job performance.